Vacuum neutralization of detergents



Oct. 7, 1952 A. c. STONEMAN VACUUM NEUTRALIZATION OF DETERGENTS 2SHEETS-*SHEET 1 Filed June 12, 1950 *"ALKANE WEIGH TANK HEAT EXCMNGERHOLDING DEAERATOR INVENTOR.

SPRAY DRYER NEUTRALIZER RECEIVER WEIGH TAN Oct. 7, 1952 A. CJSTONEMANVACUUM NEUTRALIZA'I ION OF DETERGENTS 2' SHEETS-SHEET 2 Filed June 12,1950 IN V EN TOR.

Patented Oct. 7, 1952 STATES PATENT OFFICE- VACUUM NEUTRALIZATION OFDETERGENTS Alan C. Stoneman, San Marino, Calif., assignor to Pine:Corporation, Ltd., South Gate, Calif., a corporation of CaliforniaApplication J unc 12, 1950, Serial No. 167,642

13 Claims. 1

This invention relates generally to improved methods for the productionof organic compounds suitable for use as detergents, and particularlythe alkali metal salts. of organic sulfonates and sulfates, which havedesirable detergent proper- In many of its major aspects the inventionis concerned'primarily witha novel and highly advantageous method foreffecting neutralization of a sulfonatedor sulfated stock, all in amanner facilitating and benefiting not only the neutralization stageitself, butalso resulting in the production of a detergent salt, theproperties and condition of which permit further processing, as in afinal spray drying stage, to give a superior quality commercial product.

At the outset it maybe mentioned that the invention contemplates the useor processing of any suitable organic sulfonates or sulfates, or

mixtures thereof, the molecular structures of which following alkalimetalneutralization, display detergent properties. Since various classesof such compounds are well known, it will sufflce to indicategenerallyjtheir types and structures. Broadly, such compounds may beregarded as organic sulfates orfsulfonates"containing an aliphatic oralicyclicj part which may or may not be attached to anaromatic'ring,with the aliphatic or alicyclic part being" derived from compoundscontaining 8- 18 carbon atoms and capable of either direct reaction'tothe sulfates or sulfonates, or indirect reaction by combination with anaromatic ring which in turn is capable of reaction to an organic sulfateor, organic sulfonate. Ex-

amples of such reactive 'alkyl radical-containing compounds are found inthe 8-l8 carbon olefins, alcohols, fatty acids, alkyl halides, andesters in the aliphatic or alicyclic series. The sulfonic and sulfuricacid derivatives of these compounds may be designated in the followinggroups: (1) Organic compounds of the general formula RFos a-orrbranched, symmetrical or non-symmetrigg] st 1 f taining 8-18 carbonatoms.

fate, dodecane-2-benzene hydrogen sulfate, or in general mixtures inwhich the 8-18 carbon alkyl radical is derived from aliphatic oralicyclic compounds of either straight or branched, symmetrical ornon-symmetrical structure. (3) Organic compounds of the general formulawherein R" is an aliphatic or 'alicyclic' radical containing 8-18 carbonatoms. Examples of this class are dodecane-l-sulfonic acid, undecane-2-sulfonic acid, hexadecane-8-sulfonic acid, or in general mixtures inwhich the 8-18 carbon alkyl radical is derived from aliphatic oralicyclic compounds of either straight or branched, symmetrical or nonsymmetrical structure. (4) Organic compounds of the general formulawherein R' is any benzenoid hydrocarbon radical having two or morereplaceable nuclear hydrogen atoms (as derived from benzene, toluene,xylene), and at least one nuclear hydrogen atom replaced by an aliphaticor alicyclic radical con- Examples of this class are the arylsubstituted alk'anes described in Lewis Patents No. 2,477,382 and'No.2,477,383. Other examples are n-dodecyl benzene sulfonic acid, n-dodecyltoluene sulfonic acid,"undecane- 2-benzene sulfonic acid,undecaneel-benzyl sulpounds of either straight or branched; symmetricalor non-symmetrical structure'..;l

Since, as indicated, the present invention is concerned primarily withthe neutralization stage, and steps beyond, it will be understood thatany suitable organic sulfo'nates or sulfates, or mixtures thereof,included in the designated class "erivnd or produced in any appropriatemanadditives, to a desirably high density commercial.

product. It has been found that the temperature of neutralization,reaction rates, admixture of the reactants and simplicity in the overallneutralization operation, are obtainable by 'conducting theneutralization of an aqueous solution of the reactants under lowpressures and temperatures maintained within a range that is found tohave a significant relation to the most desirable qualities of theneutralization product.

In accordance with. the invention, provision .is made for contacting and1-intimately .admixing the acid sulfonated or .sulfated hydrocarbon'stockwith a suitable alkaline neutralizingsolution; preferably: .alkalimetal hydroxide solution,

:under *conditions effecting such completeness .and intimacy of contactas willpromote complete reaction to the point .of neutralization andformation of the detergent alkalimetal salt. Of

critical importance .is the maintenance of the reactants under lowtemperatureconditions assuring stabilization .-of the desired molecularstructure of the-salt, and'at low pressure resulting in the freeing ofvolatiles from the material, all to the end that the productwill be ofhigh quality with respect to color andfreedomirom excessivecontaminants. .Of further importance in relation to final drying ofaneutralized slurry,

is the formation and maintenance of theslurry during neutralization,under low pressureand temperature conditions within particular rangesthat have been found to result in desirably high .densityof the finishedproduct.

' The neutralization stage preferably .is conducted byfirst intimatelyadmixingthe .acid' stock and caustic solution inturbulent and highvelocity streamswithin a small mixing zone from which the resultingmixture issprayed andatomized in'finely divided'formwithin an evacuatedchamber maintained at a low ,absolute' pressure within the range ofabout-9 to 88 mm. of mercury and at a corresponding water vaportemperature within a range of about 50 F. to 120 F. It-is found thatoperating within this pressure and temperature rangegivesto theneutralized salt the desirable-light color and purity referred to in'the foregoing,- and tothe resulting slurry a viscosity maintainablewithin the range .of:500 to 1500.centipoises at 100 .F., contributing tothe desirably high .density of the finished product. To. assure, mostefficient distribution 'andintimacy of contact between the reactants atthe point of their admixture, as within .a spray nozzle, provisionismade formaintaining ;a continuous. recirculationof the slurry into thenozzle, the. slurry constituting an alkali carrier as a dispersing andsolubilizing medium for promoting fine particle division andreaction ofthe acidic and alkalinematerials.

According to :a preferred method of eration, the neutralization processis started using 'a measured quantity of caustic solution placed in thevessel or vessels constituting, .in

" effect, the low pressure neutralizingzone, alkali content-ofthe'solution being substantially the in the mixture. slurry moreparticularly dealt with stoichiometrical equivalent of a measuredquantity of the acidic stock to be neutralized. At the start of andthroughout neutralization cycle, the acid stock is fed at a measuredrate to a stream of the caustic solution being continuously recirculatedfrom an accumulated body in the'low pressure zone to the spray nozzle,all

ina manner such that'as neutralization progresses, the caustic solutionacquires increasing quantities of the neutralized salt, and thecharacter of a slurry, while the solution or slurry continuously loseswater by reason of the low pressure-induced vaporization. At all timesdur- ;ing.zthe.neutralization however, the slurrycontains-reactivealkali at concentrations which are at least sufficientfor complete neutralization of the acid stock. Thus, recirculation ofthe slurry and feeding of the acid stock continue until the entiremeasured quantity of the latter is taken into the neutrallzer.

Thereafter, the, neutralized residue may be iven any f-urtherndesireddisposition or treatment. .-Preferab1y,,.I control the neutralization,to produce a final slurry having a viscosity within .the indicatedrange, which then may be spray dried, ordinarily following addition tothe slurry of suitable builders or.fillers. While as previouslyexplained, the .slurry is advantageously preconditioned bythe presentmethods to provmote formation of a .desirably high density spray-driedproduct, it is found that the quality of the product in this respect maybe further improved by. subjecting the slurry, and followingincorporation therein .of any. additives, to a final deaerationatsufficiently. low pressure to effect the removal of air and volatilespresent Thisifinal .deaeration of the m copending application 'Ser. No.167,086 entitled Deaeration, and Drying of. Water-SolubleSulfonatedDetergent Compositions, and filed on even date herewith.

...-.All tlie'various features and objects of the invention, as .well asthe details of certain typical and illustrativeprocedures. will beexplained to best.,adva'ntage 'in the following description of theaccompanying drawings, in which:

vFig.1 is a flow sheet illustration. of the process; ,Fig..2.isajfragmentarysectional view of the neutralizer chamber;

Fig. .3is an enlarged fragmentary section on line 3--3..of, Fig.2; and

Fig. l is a cross section on line 44 of Fig. 3. Merelyas illustrative ofthe derivation of the acidic hydrocarbon stockv to be treated, Fig. 1showsia preliminary sulfonation stage employ .ing weighing tanks!!! andI I, the former containing any suitable alkane, i. e., sulfonatable orsulfatable hydrocarbon. .or hydrocarbon mixtures'jtypicelly.a. mixtureof benzenoid hydrocarbons. having two. or. more hydrocarbon atoms,replaceable by sulf-onation, the benzenoid radical having an attachedalkyl group containing 8 to 18 carbon atoms. Tank Il may contain 25%JSOllllliOHOLOlGllIll. From the weigh tanks, the :alkanezand-acidarefed'through lines l2 and I3 to :thegsulfonator M wherein thematerials are subjectedqtosuitable mixing and mechanical agitation.:Fromthe sulfonator the mixture is pumped through line I 5 and the watercooled heat exchanger IE to be recirculated back into the sulfonatorthrough line ll. When the sulfonation-is-complete, the material ispumped through lines {8 into one or the other of the holding tanks [9.The latter thus will be understood to contain a predeterminedquantity ofthe inlet passage 40.

5. sulfonate of known total acidity. Delivery of the sulfonate from oneor the other of tanks Hi to the neutralizer, generally indicated at 20,occurs through line 21 containing the pump 22.

The neutralizing equipment in its entirety is regarded as including aclosed chamber 23 communicating through line 24 with one ,or the otherof the closed receiver weigh tanks 26 and 21, the latter being locatedbelow chamber 23 a distance at least as great as the height of abarometric water leg, and for example about 40 feet. With chamber 23evacuated in the manner already explained, and in communication withtanks 26 or 21 through line 24, the neutralizer chamber and the weightank in communication therewith during a neutralizing operation, maytogether be regarded as constituting the entire neutralizing zone, andchamber the low pressure part of the neutralizing zone. The solution orslurry in the chamber 23 may dis-charge downwardly by gravity throughline 24 into the weigh tank, in which event line 24 may take the form ofa straight vertical barometric leg. Or for such purposes as to economizein the structural or building height required to accommodate theneutralizer equipment in a vertical distance less than the height of abarometric leg, I; may discharge the slurry from the neutralizer downinto the weigh tank by one or a series of pumps in branch 24a of line24, withbranch 24b closed or eliminated. As will be understood,xthedisplacement capacity of the pump or pumps will be sufficient formaintenance of the specified pressure conditions in chamber 23.

The sulfonated stock is delivered from line 2| into an annular header 28at the top of the neutralizing chamber 23 and from which the stock isfed through branches 29 to spray heads or nozzles (typically four),generally indicated at 30, mounted in circularly spaced arrangement inthe headof the chamber. Referring to Fig. 4, each spray head comprises anozzle 3| threaded into an opening 32 in the chamber shell and having aninside concave face 33 to which fluid is discharged from an upperconcavity 34 in the nozzle, through opening 35. Each spray head has abody 36 threaded at 31 on the nozzle and containing a mixing chamber 38in axial alinement with the nozzle. The sulfonate is discharged fromheader 28 through fitting 39 and passage 40 tangentially into thechamber 38.

As will appear, continuously during the neutralization, a quantity ofthe solution or slurry contained in one or the other of tanks 26 and 21in use at the time is recirculated to the spray heads by pump 4| throughline 42 connecting with header 43. From the header, the slurry isdischarged through branches 44, fitting 45 and passage 46 leadingtangentially into the mixing chamber 38, at 90 degrees from thesulfonate The two streams thus being discharged through the restrictedpassages and 46 tangentially and in the same direction within chamber 38undergo turbulent and thorough mixing, with intimacy of contact betweenthe reactants being promoted by reason of the solubilizing anddispersing functions of those components of the recirculated stream inaddition to the caustic. Since the rate of delivery of the recirculatedstream to the mixing chamber 38 is desirably in volume excess over therate of sulfonate delivery thereto, passage 46 may be made somewhatlarger than the bore 40.

Chamber 23 and the communicating receiver 26 or 21, are evacuated as byway of a head 48 connected to the shell vapor outlet 49 and com- 6.municating through duct 50 with the conventionally illustrated steamejector 5|. As previously indicated, the absolute pressure withinchamber 23 and the communicating weigh tank is maintained within a rangeof 9 to 88 mm. of mercury, at which pressure the temperature of theslurry becomes established in accordance with the cooling effect of thewater vaporization within the range of about 50 to 120 F. By reason ofthe lowpressure in the neutralizer and the form of the nozzles 3 I,therecirculated slurry components are discharged in finely atomizedspray patterns within chamber 23, and the resultant slurry is taken ondown through line 24 into the weigh tank. Water vapor formed in the lowpressure chamber is drawn off to the ejector through outlet 49, belowwhich is mounted a baffle 491 to prevent spray loss.

At this point it may be mentioned that preparatory to the neutralizingcirculation, a weighed quantity of solution containing caustic soda in aquantity substantially stoichiometrically equivalent to the sulfonate,is. contained in one of the tanks 26 or 21. At the start ofneutralization, the recirculated stream is caustic soda solution, and asneutralization continues with formation of the sodium sulfonate salts,the caustic solution becomes progressively a slurry of increasing saltconcentration, until finally at the point of neutralization of all thesulfonate charge, substantially all the caustic may have becomeconsumed. At this stage of complete neutralization, the slurry and tank26 or 21 is brought within a viscosity range of from 500 to 1500centipoises at 100 F.

The following is a tabulation of data in a typical run:

Table I Alkane in tank l0 10,000 lbs. 25% oleum in tank H 10,775 lbs.25.4 Baum caustic soda solution 39,230 lbs.

(19.5%) in receiver 26 or 21. Acid addition time to sulfonaton- 14 hrs.35

- mm. Maximum temperature during 93 F.

acid addition to sulfonator. Maximum temperature during di- 94 F.

gestion in sulfonator. Time of sulfonic acid delivery to 12 hrs. 25

' neutralizer. min. Total potential amount of water 35,000 lbs.

available. Total water removed by evapora- 4,400 lbs.

tion. Average flow rate of sulfonic acid 2.5 gals. per

to neutralizer. min. Approximate recirculation rate of 40 to gals.caustic and slurry. per min. Neutralizer chamber temperature to 120 F.Vacuum chamber absolute pres- 12 to 31 mm. sure. mercury.

The slurry produced was found to have approximately the followinganalysis:

Table II Active detergent content per cent..- 27.3 Salt Cake (NazSOc)per cent 21.2 Unreacted stock per cent 0.3 pH of slurry 8.3 Reflectancecolor 73 Viscosity at F c. p. s 900 Considering now further treatment ofthe slurry, following completion of the neutralization cycle, theslurryis taken from tank 26 or 2lgby way of line 55 and isdlscharged-by pump56 through line 51 into :an appropriate mixer 58, wherein there may beadded to the'slurry any suitable builder or builders (such as soda ash,sodium bicarbonate, alkali-metalsilicate, borax, alkali metal phosphate,sodium citrate or sodium carboxy methyl. cellulose), together with anyof the usual fillers (such as sodium sulfate, sodium chloride, fullersearth or'silica) L. As illustrative, the mixer 38 isshown to have anadditive'inlet 59 and to contain a suitable agitator El. During themixing, air is introduced to and retained by the mixture in quantitiestending to lower the density of the final spray dried product below thehigher density desired for the active concentration of the product.

This condition is cured by discharging the mixture by pump 6! throughline 62 into a deaerator 63 comprising an enlarged chamber evacuatedthrough line 54 tdmaintain within the chamber an absolute pressurewithinthe range of about from 50 to 250 mm. of mercury. The mixture isdischarged into the chamber through an appropriate spray head 65 so thatthe materials become finely dispersed and therefore efficientlydeaerated in the low pressure atmosphere. From the deaeratonthe slurryis discharged by pump 66 throughline- Bl into a spray drier 68, forexample of 'the'type Shown in my copending application "Ser. No. 72,427,on Spray Drier, filed January 24, 1949. In the' drier the slurry isair-dispersed and dehydrated to form a finished granular productcontinuously discharged at 69 from the bottom of the drier.

I claim:

l. The method of neutralizing an acidic stock of the class consisting ofsulfonated and sulfated organic compounds having an aliphatic radicalcontaining between about 8 to 18 carbon atoms 1 and the alkali metalsalts of'which have detergent properties, that includes converting saidstock to a slurry of a water dispersable alkali metal salt thereof bydischarging a mixture of said stock and an aqueous solution of an alkalimetal hydroxide in finely divided form openly and through an extendedpath within the atmosphere of a zone maintained at an absolute pressurebetween about 9 to 88 mm. of mercury and at a temperature between about50 to 120 F., V

cury and at a temperature betweenabout 50 to 120 F. said stock in anaqueous mixture ,to a water dispersable alkali metal salt thereofcontained in a fiowableslurry by discharging a mixture of said stock andan aqueous solution of an alkali metal hydroxide in finely divided formopenly and through an extended path within the of the 'class consistingof sulfonated and sulfated organic. compounds having an aliphaticradical containing between about 8 to '18 carbon atoms and the alkalimetal salts of which have detergent properties, that includes convertingat an absolute pressure between about 9 to 88 mm. of mercury and at atemperature between about 50 to 120 F'.- said stock in an aqueousmixture to a water dispersable alkali metal salt thereof contained in afiowable slurry having at 100 F. a viscosity between about 500 to 1500centipoises' by discharging a mixture of said stock and anaqueous-solution of an alkali metal hydroxide in finely divided formopenly and through an extended path within the atmosphere at a zonemaintained under said pressure, limiting dehydration of the mixture toproduce a flowable slurry, and continuously flowing theslurry from saidzone during its formation.

4. The method of neutralizing an acidic stock of the class consisting ofsulfonated and sulfated organic compounds having an aliphatic radicalcontaining between about 8 to 18. carbon atoms and the alkali metalsalts of which ha /edetergent'properties, that includes discharging astream of said stock together with an aqueous alkali metal hydroxidesolution into a zone maintained at a subatrnospheric pressure betweenabout 9 to 88 mm. of mercury and, at a temperature between about 50 F.to 120 wherein the resulting mixture is cooled by water vaporizationfrom the mixture caused by the low pressure in the zone, limitingdehydration 0f the mixture to produce a fiowable slurry recirculating anaqueous slurry of reacted stock and alkali from said zone into saidstream of the stock being discharged into, said zone and flowing theproduct slurry from said zone.

5. The method of neutralizing an acidic stock of the class consisting ofsulfonated and sulfated organic compounds having an aliphatic radicalcontaining between 3 to 18 carbon atoms and the alkali metal salts ofwhich have detergent properties, that includes spraying a stream of saidstock together with an aqueous alkali metal hydroxide solution openlyand in free falling dispersion within a zone maintained at asubatmospheric pressure wherein the resulting mixture is cooled by watervaporization from the mixture caused by the low pressure in the zone,the mixture being maintained in said zone at an absolute pressurebetween about 9 to 88 mm. of mercury and at a temperature between about50 to. 120 F., repeatedly and continuously recirculating an aqueousslurry of reacted stock andalkali from said zoneinto said stream of thestock and throughout the period of its sprayed injection into said zone,and continuously depleting the water content of the recirculated slurryby the low pressure induced water vaporization to produce a fiowable andpumpable slurry.

6. The method of neutralizing a quantity of an acidic stock of theclass. consisting of detergent-forming sulfonated and sulfated organiccompounds having an aliphatic radical containing between 8 to 18 carbonatoms with an aqueous solution of a substantially stoichiometriealquantity of an alkali metal hydroxide, that includes maintaining saidalkali solution in a low pressure zone, continuously evacuating said zonand maintaining therein a pressure between about 9 to 88 mm. of mercuryand an essentially water vaporv atmosphere having a temperature betweenabout 50". F. to 120 F., continuously injecting a stream of said stockinto a relatively small mixing zone and then immediately in spray forminto said low pressure zone, continuously recirculating said alkalisolution together with neutralized acidic compounds from said lowpressure zone into said mixing zone substantially throughout injectionof said stock into the zone so that the alkali solution and neutralizedcompound are intimately mixed with the stock and immediately sprayedtherewith into the low. pressure zone and the recirculation is continueduntil all the acidic stock is neutralized,.limiting dehydration of themixture to produce a flowable slurry, and flowing the slurry from saidzone.

'1. The method of neutralizing an acidic detergent-forming stockcomposed predominately of a mixture of benzenoid hydrocarbons in whichthe benzenoid radical has an attached alkyl group containing between 8to 18 carbon atoms and has at least one hydrogen atom replaced by an-OSO2OH radical, that includes converting said stock to a slurry of awater dispersable alkali metal salt thereof by discharging a mixture ofsaid stock and an aqueous solution of an alkali metal hydroxide infinely divided form openly and through an extended path within theatmosphere of a zone maintained at an absolute pressure between about 9to 88 mm. of mercury and at a temperature between about 50 to 120 F.,limiting dehydration of the mixture to produce a flowable slurry, andflowing the slurry from said zone.

8. The method of neutralizing with a quantity of an alkali metalhydroxide a substantially stoichiometrical quantity of an acidicdetergentforming stock composed predominately of a mixture of benzenoidhydrocarbons in which the benzenoid radical has an attached alkyl groupcontaining between 8 to 18 carbon atoms and has at least one hydrogenatom replaced by an -OSO2OH radical, that includes maintaining saidalkali solution in a lower collecting zone, continuously injecting astream of said stock into a relatively small mixing zone and thenimmediately in spray form into an enlarged low pressure neutralizingzone above the collecting zone and from which the sprayed materialpasses into the collecting zone, continuously recirculating said alkalisolution together with neutralized stock from said collecting zone intosaid mixing zone substantially throughout spraying of said stock intothe zone so that the recirculated alkali and neutralized stock areintimately mixed with and in larger quantity than the stock andimmediately sprayed therewith into the low pressure zone, continuouslyevacuating said neutralizing zone and maintaining the material thereinat a pressure between about 9'to 88 mm. of mercury and at a temperaturebetween about 50 F. to 120 F., continuously depleting said slurry of itswater content by virtue of the existent pressure to produce a flowableslurry having a viscosity at 100 F. between about 500 to 1500centipoises, and continuously flowing said slurry from said neutralizingzone downwardly into the collecting zone.

9. The method of producing a detergent product from a base stock of theclass consisting of sulfonated and sulfated organic compounds having analiphatic radical containing between about 8 to 18 carbon atoms and thealkali metal salts of which have detergent properties, that includesconverting said stock to an aqueous slurry of a water dispersable alkalimetal salt of the stock by discharging a mixture of said stock and anaqueous solution of an alkali metal hydroxide in finely divided formopenly and through an. ex-' tended path within the atmosphere of a zonemaintained at an absolute pressure between about 9 to 88 mm. of mercuryand at a temperaturebetween about 50 to 120 FE, limiting de-p sulfonatedand sulfated organic compounds hav,-- ing an aliphatic radicalcontaining between 8 to 18 carbon atoms and the alkali metal salts ofwhich have detergent properties, that includes converting said stock toan aqueous slurry of a water dispersable alkali metal salt of the stockby spraying a mixture of said stock and an aqueous solution of an alkalimetal hydroxide in finely divided form openly and through an extendedpath within the atmosphere of a zone maintained at an absolute pressurebetween about 9 to 88 mm. of mercury and at a temperature between about50 F. to 120 F., limiting dehydration of the mixture to produce aflowabl slurry, mixing solid additives with the slurry, deaerating theresulting mixture at an absolute pressure between about 50 to 250 mm. ofmercury, and spray drying the deaerated mixture.

11. The method of neutralizing an acidic stock of the class consistingof sulfonated and sulfated organic compounds having an aliphatic radicalcontaining between about 8 to 18 carbon atoms and the alkali metal saltsof which have detergent properties, that includes converting said stockto a slurry of a water dispersable alkali metal salt thereof by sprayinga mixture of said stock and an aqueous solution of an alkali metalhydroxide in finely divided form openly and through an extended pathwithin the atmosphere of a zone maintained at an absolute pressurebetween about 9 to 68 mm. of mercury and at a temperature between about50 to 120 F., limiting dehydration of the mixture to produce a flowableslurry, flowing the slurry into a drying zone and therein spray dryingthe slurry to produce a granular product.

12. The method of neutralizing an acidic detergent-forming stockcomposed predominately of a mixture of benzenoid hydrocarbons in whichthe benzenoid radical has an attached alkyl group containing between 8to 18 carbon atoms and has at least one hydrogen atom replaced by an--OSO2OH radical, that includes converting said stock to a slurry of aWater dispersable alkali metal salt thereof by discharging a mixture ofsaid stock and an aqueous solution of an alkali metal hydroxide infinely divided form openly and through an extended path within theatmosphere of a zone maintained at an absolute pressure between about 9to 88 mm. of mercury and at a temperature between about 50 F. to 120F.,1imiting dehydration of the mixture to produce a flowable slurry,mixing a solid additive with the slurry, and spray drying the resultingmixture.

13. The method of neutralizing an acidic stock of the class consistingof sulfonated and sulfated organic compounds having an aliphatic radicalcontaining between about 8 to 18 carbon atoms and the alkali metal saltsof which have detergent properties, that includes converting said stockto a slurry of a water dispersable alkali metal salt I thereof byintimately mixing the acidic stock and 11; 12'; ti-velysmall mixing;zonmthensuddenly dis- REFEREN.CES."CITED chargingthe\hig1i:ve1ocity1mixturein finely divid- The foll i references are ofrecord in tha edflform openly-andtthrough anextended path fileoithispatent: withinthe atmosphere of. an enlarged zone maintained'at anabsolute pressure between about 9 v 5; UNITED STATESPATENTS' to: 88 mm.of mercurytand at a temperature bee Number Name Date tween-'.ab'out-:5-0F.' to 120 F. at which the mix- 1,968,797 Bertsch.. Ju-1y31, 1934ture-particlesundergo cooling-by virtue of Water 2,162,269: MikeskaJune-.13, 1939 vaporization therefrom induced by the low pres-2,187,244" Mills Jan. 16, 1940 sure, Iimitingdehydfatmn of the mixturein said 10 2,20 ,037" H nk1 ne 4 zoneto produce a-- flbwable slurry,and'fl'owing 2,316,670 Colgateet a1; Aprp13, 1943 the slurry fromsaidzone.

ALAN "C; STONEMAN.'

1. THE METHOD OF NEUTRALIZING AN ACIDIC STOCK OF THE CLASS CONSISTING OSSULFONATED AND SULFATED ORGANIC COMPOUNDS HAVING AN ALIPHATIC RADICALCONTAINING BETWEEN ABOUT 8 TO 18 CARBON ATOMS AND THE ALKALI METAL SALTSOF WHICH HAVE DETERGENT PROPERTIES, THAT INCLUDES CONVERTING SAID STOCKTO A SLURRY OF A WATER DISPERSABLE ALKALI METAL SALT THEREOF BYDISCHARGING A MIXTURE OF SAID STOCK AND AN AQUEOUS SOLUTION OF AN ALKALIMETAL HYDROXIDE IN FINELY DIVIDED FORM OPENLY AND THROUGH AN EXTENDEDPATH WITHIN THE ATMOSPHERE OF A ZONE MAINTAINED AT AN ABSOLUTE PRESSUREBETWEEN ABOUT 9 TO 88 MM. OF MERCURY AND AT A TEMPERATURE BETWEEN ABOUT50* TO 120* F., LIMITING DEHYDRATION OF THE MIXTURE TO PRODUCE AFLOWABLE SLURRY, AND FLOWING THE SLURRY FROM SAID ZONE.